Apparatus for stacking sheet-like products, in particular printed products

ABSTRACT

A preliminary stacking device ( 22 ) is arranged above the stacking shaft ( 12 ) of the stacking apparatus ( 10 ). This device has a preliminary stacking shaft ( 24 ) to which sheet-like products ( 30 ) are fed by way of the feed means ( 28 ). A number of sheet-like products ( 30 ) is stacked in each case on base elements ( 50 ) to form an intermediate stack ( 20 ), whereupon the intermediate stacks ( 20 ) are transferred to the stacking shaft ( 12 ). A number of base elements ( 50 ) are arranged one behind the other along a circulatory path ( 51 ), a working portion ( 85 ) of the movement path ( 51 ) of the base elements ( 50 ) running vertically through the preliminary stacking shaft ( 24 ). While an intermediate stack ( 20 ) is being formed on one base element ( 50 ), the base element ( 50 ) arranged beneath discharges a previously formed intermediate stack ( 20 ) to the stacking shaft ( 12 ).

FIELD OF THE INVENTION

The present invention relates to an apparatus for producing stacks of sheet-like products, in particular printed products, according to the preamble of patent claim 1.

BACKGROUND

An apparatus of this type is known, for example, from EP 1 439 143 A1. It has a stacking apparatus with a stacking shaft, above which a preliminary stacking device is arranged. The preliminary stacking shaft of the preliminary stacking device is bounded on all four sides by means of guide profiles and at the bottom by two slide plates which can be moved in and out of the preliminary stacking shaft from the side. Intermediate-base elements designed for example in a fork-like manner can be moved in and out of the preliminary stacking shaft from the side at a distance above the slide plates.

An apparatus of the same construction is also disclosed in EP 0 586 802 A and U.S. Pat. No. 5,370,382. The functioning of all these known apparatuses is described in detail in the two last-mentioned documents.

BRIEF SUMMARY OF THE INVENTION

It is an object of the present invention to develop the known apparatus such that, while operating smoothly, a high processing capacity is ensured.

This object is achieved by an apparatus which has the features of patent claim 1.

Whereas, in the case of the apparatuses which are known from the abovementioned documents, the intermediate-base elements and slide plates, which correspond to the base elements of the present invention, are moved horizontally into the preliminary stacking shaft from the side, and moved out of the same in the opposite direction, according to the invention the base elements are moved along a continuous circulatory path and are moved through the preliminary stacking shaft at least more or less vertically. This ensures smoother operation of the apparatus and allows problem-free separation of the sheet-like products, in particular if they are fed in an imbricated formation. Of course, it is also possible for the sheet-like products to be fed to the preliminary stacking shaft in sections, or at a distance one behind the other, by way of feed means.

A preferred embodiment of the apparatus according to the invention as described in claim 2 makes it possible for one base element to be brought into a standby position in the vicinity above the feed means while an intermediate stack is being formed on the immediately preceding base element, dropping of the fed products being avoided in the process, by virtue of this base element being lowered continuously, and for the first-mentioned base element then to be brought very quickly out of the standby position into a receiving position at the feed means.

A further preferred embodiment of the apparatus according to the invention as described in claim 3 makes it possible to achieve a high processing capacity using only two first and two second base elements.

A particularly preferred embodiment of the apparatus according to the invention as described in claim 4 allows optimum control of the pivoting position of the base elements.

Further particularly preferred embodiments of the apparatus according to the invention are specified in the rest of the dependent patent claims.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

The invention will be explained in more detail with reference to an exemplary embodiment illustrated in the drawing, in which, purely schematically:

FIG. 1 shows a side view of an apparatus according to the invention having a stacking apparatus with a stacking shaft, and having a preliminary stacking device which is arranged above the stacking apparatus and has a feed means for feeding the sheet-like products which are to be stacked;

FIG. 2 shows, likewise in side view and on an enlarged scale in relation to FIG. 1, part of the apparatus according to the invention from FIG. 1 with a circulatory arrangement for base elements of the preliminary stacking device; and

FIG. 3 shows the circulatory arrangement as seen in the direction of the arrow III from FIG. 2 and partly in section.

DETAILED DESCRIPTION OF THE INVENTION

As can be seen from FIG. 1, the apparatus according to the invention has a stacking apparatus 10 with a stacking shaft 12 which is bounded on all four sides by profiles 14 and at the bottom by a raisable and lowerable stacking table 16. The stacking shaft 12 can be rotated through 180° in each case about a vertical axis 18 in order for it to be possible for intermediate stacks 20 to be received in a state in which they are offset through 180° in each case in relation to one another. If a completed stack comprising at least one intermediate stack 20, but preferably a plurality of intermediate stacks 20, has been formed in the stacking shaft 12, the stacking table 16 is lowered to the full extent and the completed stack is pushed out of the stacking shaft 12 in a generally known manner. It should be expressly mentioned in this context that the stacking apparatus may also be designed in the manner disclosed in EP 1 445 224 A.

The stacking apparatus 10 has arranged above it a preliminary stacking device 22, of which the preliminary stacking shaft 24 is located above the stacking shaft 12 and is aligned therewith. The preliminary stacking device 22 has a feed means 28 which is designed as a belt conveyor 26 and is intended for feeding sheet-like products, in the present case folded printed products 30 such as newspapers or periodicals, to the preliminary stacking shaft 24. The belt conveyor 26 has a conveying belt 32, which is driven in circulation in the feed direction Z, and a pressure-exerting belt 34, which is arranged above the conveying belt, the two belts together forming a conveying gap 36 for the printed products 30. The printed products 30 rest in an imbricated formation S on the conveying belt 32, each printed product 30 resting partially on the preceding printed products 30, as seen in the feed direction Z. The conveying gap 36 terminates at the top end 38 of the preliminary stacking shaft 24, as seen in the feed direction Z, and the printed products 30 are therefore fed laterally and from above the preliminary stacking shaft 24.

On the side which is located opposite the feed means 28, as seen in the feed direction Z, the preliminary stacking shaft 24 is bounded by a vertically running stop strip 40, against which the printed products 30 freed from the conveying gap 36 come into abutment by way of their leading edge 42. On the side which is directed toward the feed means 28, the preliminary stacking shaft 24 is bounded by a planar wall element 44, which can be adjusted by means of an adjusting element 46, for example a cylinder/piston subassembly, in accordance with the format of the printed products 30 which are to be processed. On the remaining two sides, which in FIG. 1 run parallel to the drawing surface, the preliminary stacking shaft 24 is bounded by further wall elements (not shown).

A circulatory arrangement 48 for base elements 50, which has a drive arrangement 47 and will be described with reference to FIGS. 2 and 3, is located on that side of the preliminary stacking shaft 24 which is situated opposite the feed means 28.

The circulatory arrangement 48 has four base elements 50 arranged one behind the other along a circulatory path 51, a first base element 52 and a second base element 54 following alternately one after the other in each case. The two first base elements 52 are arranged on a first conveying mechanism 56, in the present case comprising two toothed belts 58, while the two second base elements 54 are arranged on a second conveying mechanism 60, comprising two further toothed belts 62.

In a preferred manner, and as illustrated in the drawing, the base elements 50, 52, 54 are mounted on their conveying mechanisms 56, 60 such that they can be pivoted about an axis 64 which runs at right angles to the circulatory path 51, and thus to the direction of circulation U of the base elements 50, 52, 54. Each of the base elements 50 has two planar base parts 66 which are spaced apart from one another in the direction of the axis 64 and are fastened on a shaft 68, which is concentric to the axis 64. The relevant shaft 68 is mounted in a freely rotatable manner on bearing elements 70 which are fastened on the associated conveying mechanism 56, 60, or the corresponding toothed belts 58 and further toothed belts 62. In order to define the pivoting position of the base elements 50, a follow-on mechanism 72 is connected to each base element 50, 52, 54 and interacts with a pivot guide 74. In the present embodiment, a control lever 76 is seated in a rotationally fixed manner at both ends of each shaft 68 and has a follow-on roller 78, as follow-on mechanism 72, mounted in a freely rotatable manner at its end. The follow-on rollers 78 arranged on the same sides of all the base elements 50 are guided in a common, continuous, groove-like guide track 80; the two guide tracks 80, which are formed and arranged in a mirror-inverted manner, form the pivot guide 74. The pivoting position of the base elements 50 is controlled such that the base elements 50 are inclined rearwardly to a slight extent as seen in the direction of circulation U; in other words, on the rear side of the base elements 50, 52, 54, as seen in the direction of circulation, the base elements 50 and the conveying mechanisms 56, 60 enclose an angle which is smaller than 90°, and is preferably approximately 80°.

For the sake of completeness, it should be mentioned that the base elements 50 comprise two spaced-apart base parts 66, in order to make it possible for the stop strip 40 to be arranged in the center.

The toothed belts 58 and further toothed belts 62 are guided, at the top end 38 of the preliminary stacking shaft 24, around equiaxially arranged top deflecting rollers 82, and, at the bottom end 38′ of the preliminary stacking shaft 24, around likewise equiaxially arranged bottom deflecting rollers 84. The working strand 86, which defines a working portion 85 of the circulatory path 51 running vertically through the preliminary stacking shaft 24, runs in a vertical direction, i.e. parallel to the longitudinal direction of the preliminary stacking shaft 24, between the top and bottom deflecting rollers 82, 84. For the sake of completeness, it should be mentioned that the working strand 86 runs outside the preliminary stacking shaft 24, on that side of the stop strip 40 which is directed away from the feed means 28. From the bottom deflecting roller 84, as seen in the direction of circulation U, the return strand 88 runs obliquely upward to equiaxially mounted first return-strand rollers 90 and, from these, runs vertically upward to likewise equiaxially arranged second return-strand rollers 92 and, from these, runs horizontally back to the top deflecting rollers 82. The two first base elements 52 are arranged equidistantly, as measured in the longitudinal direction of the first conveying mechanism 56. The same applies to the second base elements 54.

The four bottom deflecting rollers 84 are arranged on a common bottom shaft 94, which is connected via a toothed-belt drive 96 to a first drive mechanism 98, in particular, as in the present case, an electric servomotor. Correspondingly, the four top deflecting rollers 82 are arranged on a top shaft 100 which, for its part, is connected via a toothed-belt drive 96′ to a second drive mechanism 98′, in the present case in the form of a further servo motor.

As can be seen in FIG. 3 by way of the keys 102, the bottom deflecting rollers 84 around which the toothed belt 58 is guided are connected in a rotationally fixed manner to the bottom shaft 94, while the two other bottom deflecting rollers 84, around which the further toothed belts 62 are guided, are mounted in a freely rotatable manner on the bottom shaft 94. The bottom shaft 94 is thus a drive shaft for the toothed belts 58 and thus for the first conveying mechanism 56 and the first base elements 52. Correspondingly, the top deflecting rollers 82 assigned to the further toothed belts 62 are seated in a rotationally fixed manner on the top shaft 100, while the top deflecting rollers 82 assigned to the toothed belts 58 are mounted in a freely rotatable manner on the top shaft 100. The second base elements 54 and the corresponding second conveying mechanism 60 are thus driven by the first drive mechanism 98.

The bearings for the shafts, the drive mechanisms 98, 98′ and the guide tracks 80 are fastened on two panels 104, which form the machine framework for the circulatory arrangement 48.

The functioning of the apparatus according to the invention will be described taking the situation illustrated in FIG. 1 as the departure point. A first base element 52 has its free end directed toward the feed means 28 at the top end 38 of the stacking shaft. The foremost printed product 30, as seen in the feed direction Z, which has already been freed from the conveying gap 36, slides on the obliquely downwardly sloping first base element 52, as seen in the feed direction Z, in the direction of the stop strip 40, by which it is then stopped and against which it comes into abutment. The following printed products 30, which are fed in imbricated formation S, slide correspondingly on the respectively preceding printed product 30, forming an intermediate stack 20 in the process, and into the preliminary stacking shaft 24. The first base element 52 is lowered slowly in accordance with the height of the printed products 30 which have already been stacked. Since this ensures identical conditions for all the printed products 30 fed, the intermediate stack 20 is formed in a neat and defined manner.

According to FIG. 1, the first base element 52 has located beneath it a second base element 54, on which a previously formed intermediate stack 20 is arranged. Starting from this position, the second base elements 54 are accelerated and moved along the circulatory path 51 in the direction of circulation U until the other second base element 54 is located in the standby position 106, which is indicated by chain-dotted lines. By virtue of the second conveying mechanism 60 being deflected around the bottom deflecting rollers 84, with control provided by the pivot guide 74, the second base element 54 loaded with the intermediate stack 20 is quickly pivoted downward and laterally out of the preliminary stacking shaft 24, as a result of which the relevant intermediate stack 20 is freed from the second base element and discharged onto the stacking table 16, or an intermediate stack 20 which has already been arranged thereon.

Once an intermediate stack 20 has been transferred to the stacking shaft 12, it can be rotated through 180° about the vertical axis 18, and this makes it possible to form a rectilinear completed stack in which the successive sub-stacks are arranged in a state in which they have been rotated through 180° in each case. For the purpose of receiving a first intermediate stack 20 in each case, the stacking table 16 is raised into a top end position, and is then lowered in each case in dependence on the height of the intermediate stacks 20. If a completed stack has been formed, the stacking table 16 is lowered to the full extent and the completed stack is pushed out of the stacking shaft in the generally known manner.

The standby position 106 is located at the top deflecting rollers 82, and thus at the top end 38 of the preliminary stacking shaft 24, as closely as possible to the feed means 28, but at a sufficient distance from the latter as to prevent any conflict during formation of the intermediate stack 20.

If an intermediate stack 20 has been completed on the first base element 52, according to FIG. 1, the second base element 54 which immediately follows this first base element 52, as seen in the direction of circulation U, and is located in the standby position 106 is moved in the direction of circulation U into the receiving position—in which the first base element 52 is shown by solid lines—in order for a further intermediate stack 20 to be formed thereon from further fed printed products 30. As the respective base element 50, 52, 54 moves from the standby position 106 into the receiving position, the base element 50, 52, 54 inserts its free end, which is directed toward the feed means 28, between two successive printed products 30, as a result of which, even in the case of a very high processing capacity, problem-free separation of these printed products 30 is ensured. The working cycle described is thus repeated as often as necessary, with first and second base elements 52, 54 alternating.

It is conceivable for more than two first base elements 52 to be arranged equidistantly on the first conveying mechanism 56 and for more than two second base elements 54 to be arranged equidistantly on the second conveying mechanism 60. Furthermore, it is also conceivable for the base elements 50 to be fixed on the relevant conveying mechanisms 56, 60. In addition, it is possible, instead of toothed belts 58, to use rail-guided carriages, with a respective base element 50 arranged thereon, and to move these carriages in the direction of circulation U by means of known drive mechanisms.

The drive mechanisms 98, 98′ can be controlled independently of one another in respect of timing in dependence on product-feed capacity, the height of the intermediate stacks 20, the number of product pages, the desired conveying capacity of products, etc. Of course, it is also possible for the drive mechanisms 98, 98′ to be operated in a manner in which they are coordinated with one another in respect of timing. The drive mechanisms 98, 98′, for example in the form of servomotors, then execute corresponding control commands in dependence on the parameters mentioned above. 

1. An apparatus for producing stacks of sheet-like products, in particular printed products, having a stacking apparatus (10) with a stacking shaft (12), and having a preliminary stacking device (22) which is arranged above the stacking shaft (12) and has a preliminary stacking shaft (24) and base elements (50) which can be moved into and out of the preliminary stacking shaft (24), it being the case that products (30) which are to be stacked to form an intermediate stack (20) are fed to one of the base elements (50) by way of a feed means (28) while an intermediate stack (20) previously formed on a further one of the base elements (50) located beneath is discharged to the stacking shaft (12) by this further base element, wherein a number of base elements (50) are arranged one behind the other along a continuous circulatory path (51), a working portion (85) of the circulatory path (51) runs substantially vertically through the preliminary stacking shaft (24), and a drive arrangement (47) drives the base elements (50) in the working portion (85) in a movement direction (U) oriented from top to bottom such that in each case one of the base elements (50) is moved to the feed means (28) when an intermediate stack (20) is being formed on an immediately preceding base element (50), as seen in the movement direction (U).
 2. The apparatus as claimed in claim 1, wherein the base elements (50) arranged one behind the other alternately form a first base element (52) and a second base element (54), the first base elements (52) are arranged on a first conveying mechanism (56) and the second base elements (54) are arranged on a second conveying mechanism (60), and the first and the second conveying mechanisms (52, 54) are driven independently of one another in each case by a drive mechanism (98, 98′).
 3. The apparatus as claimed in claim 2, wherein the drive mechanisms (98, 98′) provided are in the form of servomotors, and the drive mechanisms (98, 98′) can be controlled independently of one another in respect of timing in dependence on the following parameters: product-feed capacity, height of the intermediate stack (20), number of product pages and desired conveying capacity of the sheet-like products.
 4. The apparatus as claimed in claim 2, wherein the conveying mechanisms (56, 60) are formed by toothed belts.
 5. The apparatus as claimed in claim 2, wherein the respectively successive first base elements (52) on the first conveying mechanism (56) and the respectively successive second base elements (54) on the second conveying mechanism (60) are spaced apart by a distance which is greater than the working portion (85).
 6. The apparatus as claimed in claim 2, wherein the first and second base elements (52, 54) on the associated first and second conveying mechanisms (56, 60), respectively, are arranged such that they can be pivoted about an axis (64) running at right angles to the circulatory path (51), and each base element (52, 54) is connected to a follow-on mechanism (72), in particular a follow-on roller (78), which interacts with a pivot guide (74), in particular a pivot guide track (80).
 7. The apparatus as claimed in claim 6, wherein the pivot guide (74) pivots the first and second base elements (52, 54) at the top end (38) of the preliminary stacking shaft (24) into a receiving position, in which they run at least more or less parallel to the feed means (Z), retains them at least more or less in this working position as they move through the preliminary stacking shaft (24), and pivots them at the bottom end (38′) of the preliminary stacking shaft (24) such that the relevant intermediate stack (22) slides off from the base element (50) into the stacking shaft (12).
 8. The apparatus as claimed in claim 2, wherein the continuous first conveying mechanism (56) and the continuous second conveying mechanism (60) are guided around equiaxially mounted deflecting rollers (82, 84) in each case at the top and bottom ends (38, 38′) of the preliminary stacking shaft (24).
 9. The apparatus as claimed in claim 1, which comprises two first and two second base elements (52, 54). 